Nuclear-substituted salicylic acid and salts thereof have high antibiotic action and have been used as antibiotics (see Japanese Patent Unexamined Publication (hereinafter referred to as "J. P. KOKAI") No. Sho 62-153245). Polyvalent metal salts of a nuclear-substituted salicylic acid have been used as stabilizers for halogen atom-containing polymeric compounds such as polyvinyl chloride (see J. P. KOKAI No. Sho 56-112955). In addition, a polyvalent metal salt of a nuclear-substituted salicylic acid, in particular zinc salt thereof has been used as a developer for recording materials (see J. P. KOKAI Nos. Sho 48-98914, Sho 62-25086 and Sho 63-186729). Moreover, J. P. KOKAI No. 63-293464 which was previously filed by the instant applicant discloses that specific nuclear-substituted salicylic acids and salts thereof are suitable for use as antibiotics, stabilizers for polymeric compounds or developers for recording materials.